Unless: the problem is the opposite. We are all thinking there is slop. Maybe a lifter is too tall and causing a tiny "knock" that sounds like a tap because of the relative size.

Since my m54 taps when the oil is cold =thick I'm assuming it's lifters that aren't quite full but it could be dry cam lobes before they get sprayed by the overhead oil channels.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)